Boiler cleaner



Aug. 9, 1938. c. L. HowsE ET AL 2,126,683

BOILER CLEANER Filed Sept. 28. 1954 'Sheets-Sheet l xNyEN-rons Curfs Q/Vowse lara @o werS Y Mx ATTORNEY Aug. 9, 1938.

c. L. HowsEr-:T AL

BOILER CLEANER l Filed Sept. 225:,v 1934 5 Sheets-Sheet 2 ATTORNEY C. L. HOWSE' ET AL.

BOILER CLEANER Rlfile'd Sept. 28. 1954 5 Sheets-Sheet 4 whiff/Affili Il f www! ATTQRNEY mwa c. n.. HowsE JET A1.

Aug. 9,.

BOILER CLEANER Filed Sept. 28. 1934 5 Sheets-Sheet 5 INVE O 5' Cart/ f aNfo-e BYFrafJA 31N-H2 "5 ATTORNEY Patented Aug. 9, 1938 UNETED STATE BOILER Curtis L. Howse and CLEANER Frank Bowers, Detroit,

Mich., assignors to Diamond Power Specialty Corporation, Detroit,

Michigan Mich., a corporation of Application September 28, 1934, Serial No. '745,970

25 Claims.

This invention relates to boiler cleaners and has particular reference to a boiler cleaner of the type which is adapted to discharge jets of cleaning fluid adjacent portions oi' the boiler to be cleaned to dislodge deposits from the same.

One of the primary objects of this invention is to provide a boiler cleaner of the above mentioned character which is provided with a blower element adapted to be projected into the boiler during the blowing operation and adapted to be retracted to a stored position exteriorly of the boiler during the intervals when cleaning uid is not being discharged from the same whereby the blower element may be utilized in the hottest part of the boiler without danger of the blower element burning out.

A further object of this invention is toV provide in a boiler cleaner' of the above mentioned character, a single means which when actuated, will cause the blower element to make a complete travel into and out of the boiler, the blower element being adapted to discharge cleaning fluid during this entire travel.

The invention has as a further object the provision of indicating means which will clearly show at all times the position of the blower element.

Still further the invention contemplates the provision in a boiler cleaner of the above mentioned character of a blower element adapted when retracted to be stored in a relatively small space whereby the boiler cleaner may be installed even though the alley space between adjacent boilers or between boiler side walls and building walls is substantially limited.

Numerous other objects and advantages of this invention will become more apparent as the following description proceeds particularly when reference is had to the accompanying drawings wherein Fig. lA is a semi-diagrammatic side view of a boiler showing a boiler cleaner constructed in accordance with the teachings of this invention associated with the same;

Fig. 2 is a semi-diagrammatic sectional View taken substantially on the line 2-2 of Fig. l and showing the blower in its projected position;

Fig, 3 is a top plan view of the blower shown in Fig. 2, the parts of the blower being in fully retracted position;

Fig. l is a longitudinal sectional view taken substantially on the line l-fl of Fig. 3;

Fig. 5 is an enlarged side elevational View of the blower;

Fig. 6 is a sectional view taken substantially on the line 6 6 of Fig. 5;

Fig. 7 is a sectional View taken substantially on the line 'l-l of Fig. 5;

Fig. 8 is a diagrammatic view showing the wiring diagram of the electrical control means utilized with the blower illustrated in Fig. 2;

Figs. 9 and 9A constitute a side elevational view partly in section showing a slightly modifled form of construction;

Fig. l0 is a sectional View taken substantially on the line lilill of Fig. 9;

Fig. ll is an enlarged plan view of a portion of the structure shown in Fig. 9;

Fig. 12 is a sectional view taken substantially cn the line l-HZ of Fig. 1l; and

Fig. i3 is a diagrammatic view showing the wiring diagram of the electrical control means utilized with the boiler cleaner shown in Fig. 9.

At the high ratings at which steam boilers are now generally operated and particularly when certain types of coal are utilized, slag is formed on the lower generating tubes of the lower deck to such an extent that the gas passages between the tubes become completely blocked in a short time. Because of the high temperatures in the fire box below these tubes, it is impossible to utilize any device for removing this slag that cannot be withdrawn or otherwise removed between blowing or cleaning periods. The present invention therefore contemplates the provision of a projectable and retractable blowernozzle or element which is exposed to the high temperatures within the boiler only during the blowing period when the cleaning fluid used is wample to keep all the exposed parts at a temperature well below that at which they would be damaged.

Further, since the available alley space between boilers or between boiler side walls and building walls is frequently quite limited, it is important that the blower element require a minimum amount of space in its retracted position. The present invention therefore provides a telescopic blower element which, when retracted, projects exteriorly of the boiler only a short distance.

Referring then particularly to the drawings wherein like reference characters designate corresponding parts throughout all views, there is diagrammatically illustrated in Fig. 1 of the drawings a standard type water tube boiler designated generally by the reference character i5. As illustrated, this boiler includes a casing I6, a cross drum il, upper and lower decks of generating tubes designated by the reference characters i8 and |9 respectively, and a superheater 20. The numeral 2| designates generally the fire box or combustion space of the boiler located as illustrated, directly below the lower deck I9 of the generating tubes. To maintain these tubes clean, a blower 25 is located approximately in the position illustrated in the drawings, this blower being constructed in accordance with the teachings of this invention.

Referring now particularly to Figs. 2, 3 and 4 of the drawings, wherein the blower 25 is shown more in detail, the numeral 26 designates a boiler wall, this Wall being provided with an opening 21, in which a Wall box 28 is mounted. Secured to this wall box and projecting exteriorly of the boiler wall is a housing 29 and secured to this housing and projecting away from the boiler wall is a cylindrical casing 3U to the outer end of which is secured a cap 3|.

Fixed, as by welding or the like to the cap 3| and projecting longitudinally of the housing 29 and casing 39, is a pipe or conduit 35. The outer end of this pipe projects beyond the cap 3| and is threaded as at 3B to provide for the attachment thereto of a cleaning iiuid supply pipe. The pipe 35 is on its exterior surface, threaded throughout its length as designated by the reference character 3l and is also provided with a longitudinally extending keyway 38, for a purpose which will hereinafter be more fully described.

The numeral 40 designates a bearing which is slidably mounted on the pipe 35 but which is held against rotation with respect to this pipe by a key 4|, which engages in the keyway 38 in the pipe 35. Fixed to the bearing 48, as at 42, and surrounding the pipe 35 is a tube 43, this tube being also threaded throughout its length as designated by the reference character 44. It will be apparent that the tube 43 is xed against rotation by virtue of its connection through the bearing 48 to the non-rotatable pipe 35 but that the tube 43 may move longitudinally with reference to the pipe 35.

The blower element proper comprises a nozzle 59 and tube sections 5| and 52. The nozzle 50 is provided with oppositely directed discharge orifices 53 and the nozzle is secured as by welding or the like, to the inner end of the tube 5|. The opposite end of tube 5| is secured to a nut 54 which engages the threads on the tube 43. Further, the tube 5| is provided in its outer surface with a longitudinally extending keyway 55 in which is engaged a key 55 carried by the tube 52.

The tube 52 is secured at its outer end as at 50, to a nut 6| which has threwaded engagement with the outer surface of pipe 35. Further, the tube 52 is provided with a longitudinally extending keyway 5| in which a key 62 is engaged, this key being carried by a worm wheel 63 which is located in the housing 29. Within the wall box a suitable bearing 64 is provided to support the overhanging load of the tubes 5| and 52 when the latter are extended. Additional bearings 65 and 55 are also provided, the bearing 65 acting to reduce the friction of tube 52 turning in casing 30 and the bearing G6 being adapted to reduce the friction of tube 52 turning on stationary bearing 40.

Suitably secured to the casing 39 is a motor 19, which by means of a chain '1| drives a shaft '|2. This shaft carries a worm T3 which engages the teeth 'F4 on the worm wheel 63 to drive the latter.

With the structure as thus far described, it will be apparent that the motor l will drive Worm wheel 63 and this Worm wheel being splined as it is to tube 52 will drive the latter. Rotation of tube 52 will cause the nut 6| to travel longitudinally of pipe 35 to thus project tube 52, bearing 40, and threaded tube 43. As brought out before, tube 43 is fixed against rotation, while tube is rotated with tube 52 by virtue of the splined connection between these two tubes. Thus rotation of tube 52 will rotate tube 5| and cause nut 54 to travel longitudinally of stationary threaded tube 43. Thus it will be apparent that for each rotation of tube 52 nut 6| will travel longitudinally of pipe 35 one thread while nut 54 will travel longitudinally of tube 43 one thread. The nozzle 58 is therefore advanced a distance equal to twice the pitch of the threads on pipe 35 and tube 43 and, assuming the pitch to be one-half inch, the nozzle 50 having two outlets gives two blowings for each inch of travel. The inside diameter of tube 52 is slightly larger than the outside diameter of tube 5| and there is enough steam leaking between tubes 35 and 43 and 43 and 5| that is forced out between tube 5| and 52 to keep these tubes cool during the blowing operation. When tube 5| is fully projected beyond tube 52, it is cooled by the cleaning fluid passing through the nozzle 55.

Preferably a small amount of heavy cylinder oil is pumped into the blower through the cleaning fluid inlet before each blowing operation to provide the lubricant necessary for the moving parts of the blower.

It constitutes a feature of this invention to provide an indicating means to indicate the position of the nozzle 59 and for this purpose the following structure is provided. Suitably journalled at one side of the casing 39 and extending longitudinally thereof, is a shaft 80, this shaft being threaded throughout its length as indicated by the reference character 8|. Formed on one end of this shaft is a worm wheel 82 which is engaged by a worm 83 formed on the end of shaft 12.

Engaging the threads 8| is a nut 85 and this nut is prevented from rotating by virtue of an extension 86 which projects through a slot 81 formed in casing 88 which encloses the shaft 8|. An indicating member 89 is carried by the projection 85 and being disposed exteriorly of the casing 88 indicates at all times the position of the nozzle 58.

The nut 85 is also utilized to control the flow of electric current to the motor 'I0 and for this purpose the following structure is provided. Mounted for limited longitudinal movement in bearings 90 is a rod 9| and fixed to the ends of this rod are lugs 92 adapted to be engaged by the nut 85 when the latter reaches the ends of its travel. Also carried by rod 9| is a sleeve 93 which engages arm 94 of a yoke 95, this yoke carrying a lug 96 which engages arm 91 of a double throw switch 93. It will be apparent that as the nut 85 reaches the ends of its travel longitudinally of shaft 80 it will engage one or the other of lugs 92 and impart a slight longitudinal movement to rod 9|. This movement will cause sleeve 93 to throw arm 97 to thus actuate switch 98, the direction of movement of the switch arm 9'! being dependent upon the direction of movement of rod 9|. For manually shifting the rod 9| to effect a reversing of motor 'I9 before the blower reaches its fully projected position, if such is desired, there is provided a bell crank lever 99 pivotally mounted on a suitable bracket and so arranged that its one end may be swung into engagement with the adjacent end of rod 9| to impart movement to the same.

The switch 98 may be a standard reversing switch by which the motor 'Hi is controlled, the usual arrangement being a push button which closes the forward circuit to the motor thus causing the blower to be projected until the blower reaches its extreme projected position. The switch is then automatically actuated to reverse the motor lil thereby retracting the blower, the switch being again actuated when the blower is fully retracted to thus sto-p the motor.

The electrical circuit which controls the motor is diagrammatically illustrated in Fig. 8 as comprising the switch 98 having the actuating arm 91, this switch contro-lling contacts |00, IUI and |02. The circuit also includes a switch HB3 pref erably of the self-opening push button type this switch controlling contacts |04 and it.

Current is obtained from a suitable source by Way of conductors |06, lill and i538, conductor |08 leading directly to the motor le. Current from source |06 flows through terminal |99 to Ilil then to Ill then to coil lli) and to terminal liili and when switch |03 is closed the current ilows through terminal |95 to terminal IIl and back to conductor ID'I. This will energize the coil Iiii closing bridges II2 and H3 connecting lil@ to iid and II5 to II I thus completing the circuit to the motor from conductor Iilii and back through con-- ductor |01. At the same time current will flow from IIE to coil H9 through conductor l it thus maintaining coil Il@ energized after switch M33 is allowed to open, the coil remaining energized as long as |00 is in contact with iiiI.

To reverse the motor, switch 9i is thro-wn over by movement of sleeve 93 to break the contact between IDI and |09, de-energizing coil Iii? and breaking the contacts between m9 and lili, Mii and I Il thus stopping the motor. Contact is now made between IIBI and |92 coil lll is energized actuating the bridges I |8 to bridge terminals i i9, liga, II9b and IISG. Current now flows from source |96 to the motor by |09, M9, bridge llt and contact II9b and from source itil to the motor by contact I I I, I i9, bridge I i8 and contact H911.

With the blower in its retracted position, the several switches are in the positions indicated. The switch button ID3 which may be located at any desired point may now be actuated to close the circuit as above mentioned causing the motor to so rotate tubes 5I and 52 of the blower as to cause a forward travel of nozzle 5u to its projected position. Coil I I9 maintains the circuit closed when the push button switch is released.

As the blower reaches the end of its forward travel, sleeve 93 actuates switch 98 to close the contact between IBI and |02 and to break the circuit between IIl and IBI. This breaks the circuit to coil IIII and closes it to coil Il'i thus reversing the motor as above indicated. When the blower reaches its fully retracted position, switch 98 is again actuated to break the circuit between terminals IIII and |02 and close the circuit between terminals lill! and IGI, the circuit then being ready for a second operation. The motor however, will not again start until push button switch |03 is again closed.

In Figs. 9 to 13 inclusive, a slightly modified form of construction is illustrated. Referring then particularly to these figures of the drawings, it will be noted that the structure includes a wall box 28', a housing 29', and a cylindrical casing 30' closed at its outer end by a suitable cap 3|'.

The blower itself includes the nozzle 5t', the tube sections 5l and 52', these tube sections being associated with each other in the manner previously described and being adapted when rotated to be projected by the cooperating threaded pipes 35 and t3. As thus far described, the blower is in all respects identical with that previously described.

In this modified construction however, the tube 52 is rotated by a second tube liii, this tube being splined to the tube 52 as at lfil. The tube l'ii is rotated by a gear |22 driven by a pinion |23 Xed to the end of a shaft liii, this shaft being driven by the motor 'iii' through reduction gearing .25 and liii. It will be understood that as thus described rotation of the shaft iZll by motor 'it' will effect a longitudinal travel of the blower element to its projected or retracted position depending upon the direction of rotation of the motor.

For the purpose of manually retracting the blower in the event that the motor 'l0' should fail, there is preferably provided a sheave wheel i3d, this sheave wheel being secured to the shaft E2G as clearly illustrated in Fig. 9 of the drawings. A chain it! engaging the sheave wheel. is accessible from the oor of the boiler room in accordance with the usual practice.

For the purpose of indicating the position of the blower nozzle bij' there is provided a quadrant shaped plate L35, this plate being provided with indicia i355 which indicates in feet the eX- tent of projection of the blower nozzle 5u. Cooperating with the indicia i535 is an indicating arm or arrow l'i, the rear end of this arm being secured to a shaft i138 by which the arm is actuated. For actuating the shaft itt, the shaft i224 is provided with an elongated gear Hit adapted to mesh with and drive gears itil and liti?. Gear I4! is fixed to and drives a shaft Mld this shaft having its outer surface threaded as indicated by reference character Mii. Gear i132 has a hub which is threaded to engage the threads it!! on shaft |143 and the hub of this gear is also provided with a groove lith to receive a yoke M5. This yoke is attached to one end of arm Ill'l, the other end of this arm being secured to the shaft |38 as clearly indicated in Fig. 12 of the drawings.

In the operation of this indicating device, the shaft ill-l is driven in hired relation to the shaft |24 through the gears it@ and Mil. Gear |42 is also driven by gear itil but gears Mil and M2 have an unequal number of teeth and gear |42 is rotated on shaft ll-l so that there will always be a lateral movement of gear M2 on shaft ll. This movement of gear M2 is transmitted to the indicating arm itl and the parts are so proportioned that the position of the indicating end of arm @3l with reference to the indicia B36 accurately indicates the distance in feet the nozzle 59 is projected.

The arm itl is also utilized for controlling the supply of electric current to the motor 'itl' and for this purpose the end of arm itil is provided with an insulated tip E59 adapted to actuate switches I5I and l52 which are clamped to the edge of the plate liti. These switches are preferably removably clamped` to the plate so that they may be located in any desired position to thus control the extent of travel of the blower. As in the first described form of construction, the switches are so arranged that after the motor has been started by the momentary closing of a push button switch located at any desired point,

the blower will be projected forwardly until the limit of its forward movement is reached, whereupon switch |5| will be actuated to reverse the movement of the motor. When the blower reaches its retracted position the switch |52 will be actuated to open the reversing circuit to the motor and to stop travel of the blower in the reserve direction.

In Fig. 13 the electric circuit is diagrammatically illustrated as including the switches |5| and |52, a magnetic reversing switch designated generally by the reference character |55, a hand switch 55 for connecting the system to the source of electrical supply and suitable manually controlled switches|51, |58 and |59. The switch i51 is the starting switch, the switch |53 is a reversing switch and the switch |59 is a stopping switch and these switches are all preferably located on a panel remote from the blower wheren by the actuation of the blower may be manually controlled at the will of the operator if desired, instead of employing the automatically operating reversing and stopping switch about to be described.

Switch |52 includes contacts |65 and |66, while switch i5! includes contacts |61, |68 and |69. The arrangement is such that the motor can only be started to project the blower by momentarily actuating the push button starting switch |51. When the blower has reached the predetermined forward position, arrow |31 moves contact |68 until it contacts with contact |69, thus making contact with the reverse side of the motor magnetic reversing switch |55. On account of the interlocking construction of this switch, however, the motor is not reversed until the arm E31 has moved contact |68 far enough to break the contact of this contact |63 with contact |51. As soon as this contact is broken, however, the motor is reversed and the blower is moved to its retracted position.

As the blower reaches its retracted position, the arm 31 moves contact |65 away from contact |66 thus opening the reversing circuit and stopping travel of the blower. The blower may thereafter only be started by actuating the push button starting switch |51.

From the above it will be apparent that the invention provides a telescopic blower in which the blower nozzle makes a complete in and out travel rotating all the way during this travel and discharging cleaning fluid adjacent parts of the boiler to be cleaned. The actuation of the blower is initiated by a single means namely, the push button since actuation of this push button causes the blower to travel to its outer position and then to return to its original retracted position.

The invention further includes indicating means for indicating the projected position of the blower and means whereby the extent of projection of the blower may be varied at the will of the operator.

For the sake of convenience, the invention has been described as being embodied in a boiler cleaner for cleaning parts of a boiler. It will be apparent however, that the inventive principles disclosed may be incorporated in a device for cleaning similar' types of apparatus and it is to be therefore understood that the term boiler wherever used in the specication or claims is to be construed as meaning a fluid heater or heat transfer apparatus of any character, while the term boiler cleaner is to be construed as meaning a cleaner for cleaning any such apparatus.

While the invention has been described with some detail, it is to be understood that the description is for the purposes of illustration only and is not denitive of the limits of the inventive idea. The right is reserved to make such changes in the details of construction and arrangement of parts as will fall within the purview of the attached claims.

What we claim as our invention is:

l.. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, means for moving said blower element to said positions, means for initiating the actuation of said moving means, and means for thereafter controlling and continuing the operation of said moving means toI cause the same to move the blower element from its retracted to its projected position and to then automatically return the blower element to its retracted position.

2. In a iiuid heater cleaner, a blower element mounted for movement to projected and retracted positions, means for moving said blower element to said positions, means for initiating the actuation of said moving means, and means actuated by said moving means for thereafter controlling and continuing the actuation of the moving means to cause the same to move the blower element from its retracted to its projected position and to then automatically return the blower element to its retracted position.

3. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, a motor for moving said blower element to said positions, a driving connection between said motor and said blower element for moving the latter from the former, a control means for said motor adapted to effect a reversal of said motor after a predetermined projection of said blower element, and means connecting said control means and said driving connection to actuate the former from the latter.

l. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, a motor for alternately moving said blower element to said positions, a control means for said motor, and means actuated in synchronism with said blower element for actuating said control means to cause the latter to effect a reversal of said motor after a predetermined projection of the blower element.

5. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, a motor for moving said blower element to said positions, a control means for said motor, means including a threaded shaft and a travelling nut on said shaft for actuating said control means, and a connection between said threaded shaft and said motor for actuating the former from the latter.

6. In a iluid heater cleaner, a blower element mounted for movement to projected and retracted positions, and electrically actuated means including a motor and control means therefor for moving said blower element to said positions, said control means being responsive to movement of the blower element and acting to reverse the motor after a predetermined movement of the blower element.

7. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, an electric motor for moving said blower element to said positions, means for initiating the actuation of said electric motor, and means automatically operating after the operation of said electric motor is initiated to cause said electric motor to move said blower element to its projected position and to then reverse the electric motor whereby the same returns said blower element to its retracted position.

8. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, an electric motor connected to said blower element for moving the same to said positions, a control for said motor operating to reverse the motor after the blower element has been'projected a predetermined amount, and a driving connection between said motor and said control means for actuating the latter from the former.

9. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, means for moving said blower element to said positions, means controlling said moving means to cause the same to return the blower element to its retracted position after the blower element has been projected a predetermined amount, and means for adjusting said control means to vary the projection of said blower element.

10. In a iluid heater cleaner, a blower element mounted for movement from projected to retracted positions, a motor for moving said element to said positions, means actuated by said motor for indicating the extent of projection of said blower element, and a control for said motor actuated by said indicating means.

1l. In a uid heater cleaner, a blower element mounted for movement to projected and retracted positions, an electric motor, a driving connection between said electric motor and said blower element for moving the latter from the former, an indicating means driven by said connection for indicating the extent of projection of the blower element, a control means for said motor operating to reverse the actuation of said motor after said blower element has been projected a predetermined amount, and means for actuating said control means by said indicating means.

l2. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, an electric motor for moving said blower element to said positions, a driving connection between said electric motor and said blower element for moving the latter from the former, a threaded shaft mounted for rotation, means for rotating said shaft from said driving connection, a nut threaded on said shaft and adapted to travel longitudinally thereof upon rotation of the shaft, indicating means carried by said nut for indicating the extent of pro-jection of the blower element, means for initiating the actuation of said electric motor, a control means adapted to reverse the electric motor after the blower element has been projected a predetermined amount and adapted further to stop the actuation of said electric motor when the blower element has been retracted, and means for actuating said control means by said traveling nut.

13. In a telescopic blower, a pair of pipe sections arranged for rotation and for telescopic movement one within the other, a nozzle carried by one of said pipe sections, means for rotating said pipe sections, and means operating upon rotation of said pipe sections to move both of said pipe sections axially and to project the inner pipe section beyond the outer pipe section.

14. In a telescopic blower, a pair of pipe sections mounted for rotation and for telescopic movement one within the other, a nozzle carried by one of said pipe sections, a pair of threaded tubes fixed against rotation, and nuts carried by said pipe sections and engaging the threads of said tubes whereby upon rotation of said pipe sections both of said pipe sections are moved axially and one of said pipe sections is telescopically moved relative to the other.

15. In a telescopic blower, inner and outer pipe sections, a nozzle carried by one end of said inner pipe section, means for rotating said outer pipe section, a splined connection between said inner and outer pipe sections whereby the inner pipe section is rotated by the outer pipe section but is adapted for axial movement relative thereto, a pair of tubes disposed within said inner pipe section, said tubes being disposed one within the other and having their outer surfaces threaded, a nut iixed to said outer pipe section and threadedly engaging the outer surface of said inner tube, a nut carried by said inner pipe section and threadedly engaging the outer surface of said outer tube, and means fixing said tubes against rotation whereby upon rotation of said pipe sections the pipe sections are both moved axially while the inner pipe section is additionally moved axially relative to the outer pipe section.

16. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, a power driven means for moving said blower element toy said positions, a driving connection between said power driven means and said blower element for moving the latter from the former, a control means for said power driven means .adapted to eiect a reversal of the actuation of said power driven means after a predetermined projection of said blower element, and means connecting said control means and said driving connection to actuate the former from the latter.

17. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, a power driven means for moving said blower element to said positions, a control means for said power driven means, and means actuated in synchronism with said blower element for so actuating said control means that it causes the power driven means to retract the blower element after movement thereof to a predetermined projected position.

18. In a fluid heater cleaner, a blower element mounted for movement toprojected and retracted positions, a power driven means connected to said blower element for moving the same to said positions, and a control means for said power driven means operating to reverse the actuation of said power driven means after the blower element has been projected a predetermined amount and operating further to stop the actuation of said power driven means when the blower element has been retracted.

19. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, a power driven means for moving said blower element to said positions, means for initiating the actuation of said power driven means to cause the same to project the blower element, and control means actuated by said power driven means operating to reverse the actuation of said power driven means after the blower element has been projected a predetermined amount and operating further to terminate the actuation of said power driven means after the blower element has been retracted.

20. In a fluid heater cleaner, a blower element mounted for rotation, means operating upon rotation of said blower element to cause the same to be projected or retracted dependent upon the direction of rotation of the blower element, a power driven means connected to said blower element for rotating the same, means for initiating the actuation of said power driven means to cause the same to rotate the blower element in such a direction that the blower element` will be projected, and a control means operating to automatically reverse the actuation of the power driven means after the blower element has been projected a predetermined amount to cause the power driven means to reverse the rotation of the blower element to thus cause the blower element to be retracted, said control also operating to automatically terminate the operation of said power driven means when said blower element has been retracted.

21. In a fluid heater cleaner, a blower element mounted for movement from projected to retracted positions, means for moving said blower element to said positions, a quadrant having indicia thereon, a pointer movable relative to` said quadrant and cooperating with the indicia thereon for indicating the extent of projection of the blower element, means connecting the element moving means and the pointer for actuating the latter from the former, and means actuated by the pointer for controlling the actuation. of said blower element moving means.

22. In a fluid heater cleaner, a blower element mounted for movement from projected to retracted positions, a motor connected to said blower element for moving the same to said positions, a control for said motor operating to reverse the motor after the blower element has been projected a predetermined amount, .and means actuated in synchronism with said blower element for actuating said control means.

23. In a fluid heater cleaner, a blower element mounted for movement to a plurality of positions, a power-driven means for moving said blower element to said positions, means for indicating the extent of movement of the blower element, and a control for said power-driven means actuated by said indicating means.

24. In a fluid heater cleaner, a blower element mounted for movement from projected to retracted positions, means for moving said element to said positions, and means for indicating the extent of projection of said blower element, said means including a shaft rotatable in synchronism with the movement of the blower element, an elongated gear on said shaft, a second shaft, a pair of gears on said second shaft arranged to be driven by the elongated gear on the rst shaft, one of the gears on the second shaft being fixed to the second shaft and the other gear on the second shaft having threaded engagement with the second shaft, the last mentioned gear on the second shaft having a different number of teeth from the other gear on the second shaft, an indicating pointer, and a connection between said indicating pointer and the gear which is threaded on the second shaft whereby said pointer is actuated upon movement of the gear longitudinally of the second shaft.

25. In a fluid heater cleaner, a blower element mounted for movement to projected and retracted positions, power-driven means for moving said blower element to said positions, a control means for said power-driven means, means including an axially movable shaft for actuating said control means, abutments on said shaft, and a member movable longitudinally of said shaft upon movement of said blower element arranged to engage said abutments to axially move said shaft and thus actuate the control means.

CURTIS L. HOWSE. FRANK BOWERS. 

